Resources

Eggshells

IMPORTANT INFORMATION: This datasheet is pending revision and updating; its contents are currently derived from FAO's Animal Feed Resources Information System (1991-2002) and from Bo Göhl's Tropical Feeds (1976-1982).

Egg shells can be available in large quantities from hatcheries and from plants that shell eggs or prepare dried egg powder.

Nutritional aspects

Nutritional attributes

Approximately 84 % of the eggshell is ash of which most is calcium carbonate. Where sources of calcium are unavailable, eggshells can be sterilized, ground and used as a highly available source of calcium.

Potential constraints

Adequate heat needs to be applied to assure that all pathogenic organisms are destroyed prior feeding.

Poultry

Biological availability of calcium in eggshell meal was determined to be 93.8 % and true absorption of calcium was 96.3 % (Bao et al., 1998).

When eggshell meal was added to a commercial layer diet it was found that eggs where heavier and shells thicker (Simeonova et al., 1984). It was found that eggshell meal could be used to replace all of the limestone in layer diets or bone meal (Neri et al., 1976; Vandepopuliere et al., 1975; Walton et al., 1977). It was found to be a suitable replacement for any inorganic calcium source in application in layer diets (Zander, 1983 [?]) and performance was found to be similar or superior (Sim et al., 1983a). Eggshell meal was found to be a highly available source of calcium, with no effect on DM intake or egg production being observed (Scheideler, 1998). An extruded mixture of ground maize and centrifugated eggshells included in the diet was free of aerobic pathogens and gave the same results as the control diet for feed conversion, egg production, egg weight, egg specific gravity (Tadtiyanant et al., 1993).

IMPORTANT INFORMATION: This datasheet is pending revision and updating; its contents are currently derived from FAO's Animal Feed Resources Information System (1991-2002) and from Bo Göhl's Tropical Feeds (1976-1982).